Thanks for your help - I'm leaning towards a 17" MBP with matte screen but a similarly prices 27" iMac is also in the reckoning, but wonder how the differing processors and RAM cope with different versions of Photoshop.

My screen is Matte and i feel that this makes the images slightly softer compared to a glossy screen on an imac (Pixel peeping)

Processor coping with crunching large 16 bit .tif files?

No problems with large 16bit tifs.

Accuracy of colour representation on screen?

Macs are designed as media tools ie graphic house etc, they have a very good profiler application built into osx and colour representation is very good, though the use of a colour calibrator is always recommended.

You have potentially more RAM capacity in the iMac 16GB vs 8GB and greater hard disk capacity 2TB vs 500GB. Graphics card is also better in the iMac.

I use an older iMac 2GHz intel core duo with PS CS3 and don't really have huge time lag issues, I also run Final Cut Studio on this machine for video processing and it does the job in an acceptable time frame. However, I am not running a commercial enterprise so I can afford to wait the little bit extra it takes to process things.

The real question is where will you use the machine, always in the same place or do you want the mobility?

The iMac wins hands down for photo editting unless you need portability but do keep in mind that apart from the Mac Pro, all Macs are pretty backward with their port selection. With the 17" MBP, you get an ExpressCard slot that does help somewhat. It's also quite difficult to change the HDD in an iMac. Have you seen the 27" iMac? OSX is not resolution independent like Windows is so increasing the resolution makes everything tiny. The 27" iMac looks incredible but I found UI elements and text a bit small.

Not sure if this was the kind of info you were looking for, but all 8600m GPUs are defective (not just Apple) and mine has one. Haven't had an issue after almost 3 years but Apple has extended the warranty to 4 years on the GPU from the original 1 year. It's nice to know. Other than that, PS and lightroom all play nicely with my Mac, no issues there.

Matte/Glossy

Glossy is more aesthetically pleasing, I find matte to be closer to the printed output but that isn't a very scientific comparison. I'd say matte is more "realistic". Apple's glossy screens are the most glossy of them all. If they were the same price, I would always go with a matte screen but I'm not sure it's worth the premium.

16 bit files

Macs tend to perform similarly spec-ed to Windows machines in all the photo editing benchmarks I've seen. For the same money a Mac will always come with inferior hardware when it comes to raw performance so there you go.

Colour Accuracy

Macs are better than the average computer in this aspect but the higher end screens from Dell, HP and Lenovo do much better. Dell has a notebook that does the full Adobe RGB colour gamut. I'm pretty HP has something similar.

After using a number of Macs I don't have strong objections on glossy screens.Matte screen has less reflection, but it still will (depending on your background).Colour wise, Glossy screen is more vivid.

dubaiphil wrote:

Processor coping with crunching large 16 bit .tif files?

I don't work on .tif files.

dubaiphil wrote:

Accuracy of colour representation on screen?

Either matte or glossy, you have to calibrate your monitor. If you are really that professional, you also need to colour calibrate your printer output.

dubaiphil wrote:

I'm leaning towards a 17" MBP with matte screen but a similarly prices 27" iMac is also in the reckoning

Well, if you don't intend to carry a computer without out get the iMac, you will enjoy the benefit of extra monitor space. (Be advised that 17-inch MacBook Pro is not that lightweight.) However, you can connect an external monitor to the MacBook Pro as well as 27-inch iMac, which means you can hook up a professional-end monitor if you really want to.